wplua: move under modules/module-lua-scripting

It's unlikely that wplua will ever be useful outside the context
of module-lua-scripting, so let's move it to keep all the code in one place

modules/module-lua-scripting/api/meson.build

@@ -0,0 +1,5 @@
+m_lua_scripting_resources = gnome.compile_resources(
+    'm-lua-scripting-resources',
+    'gresource.xml',
+    source_dir: meson.current_source_dir(),
+    c_name: '_m_lua_scripting_resources')